The Banbury Center of Cold Spring Harbor Laboratory proposes the holding of a small, high-level conference bringing together a variety of approaches involved in investigation of gene regulation and the genetic control of development including introduction of specific clone genes into germ lines by microinjection or viral infection of early embryos, induction of developmental mutations in a manner permitting direct identification and cloning of the effected genetic loci, introduction of genetically altered cells into early embryos with the resultant representation of such cells in the developing animal and transfer of nuclei between embryos. Given the particularly rapid progress in these areas and the potentially far-reaching impact of the field, it is felt that present day assessment and consideration of likely future developments would be particularly appropriate in the fall of 1984. Extensive discussion is to be included as part of the conference program and edited transcripts of these discussions are to be published together with formal presentations in a volume in the on-going series of Banbury reports (Report No. 20, Spring 1985). The proposed conference program is divided into six sessions. These are: Sessions one and two, on introduction of cloned genes into mammalian embryos; session three on viral vectors and tissue specific enhancers; session four on gene transfer and non-mammalian organisms; session five on embryonal carcinoma cells, chimera formation and gene transfer, and session six on mouse genetics. Invited participants include 32 individuals listed on pages 30-32 of the application. The conference is intended to be of limited participation with the proceedings recorded and published by a third party.